Your accounting rulebook might say “IFRS” on the label, but lots of people still wonder exactly what they might find inside once they open it up.

That question is being asked more often these days, as American and European accounting rulemakers press forward with plans to converge International Financial Reporting Standards with U.S. Generally Accepted Accounting Principles. At the same time, the Securities and Exchange Commission is pondering whether to allow registrants to file financial statements in IFRS as approved by the International Accounting Standards Board—not as approved by any of the more than 100 nations now nominally in the IFRS camp.